The invention relates to an installation for refuelling an aircraft from a pressurized fuel distribution network.
1. Field of the Invention
At present there are two main methods for refuelling aircraft in airports.
A first method relates to the airports equipped with a pressurized fuel distribution system having at least one pressure intake located in the vicinity of each of the aircraft parking points. It consists of using small trucks known as servicers, which are connected to the probes of the system in order to refuel the aircraft. Each servicer constitutes an autonomous unit which is brought to the parking point when an aircraft requires refuelling. The servicer is equipped with one or more connecting hoses, a fuel filtration system, a counter, a certain number of valves and safety devices, as well as a lifting platform enabling an operator to connect the hoses to the aircraft fuel filling ports. Operation of the various equipments is ensured by in particular hydraulic and pneumatic energy sources installed on the servicer.
Although used in certain airports, this refuelling procedure suffers from important disadvantages.
More particularly, so that the energy sources available on the servicer can be used, it is indispensable for its engine or motor to remain in operation throughout refuelling. This is clearly unsatisfactory from the a safety standpoint.
In addition, servicers are expensive vehicles and consequently their number is limited for each airport. Therefore these vehicles must permanently travel from one point to another within the airport, which constitutes a potential risk for an accident and can sometimes delay flights.
In addition, the distribution of fuel by means of the servicer generally takes place by a single operator, who controls all the operations either from the servicer lifting platform, or from an external platform. This leads to relatively long response times, which means that the injection of the fuel is sometimes stopped too late and fuel is therefore discharged onto the ground by the overflows of the tanks of aircraft. This is obviously unsatisfactory both from the financial and an ecological standpoint.
Moreover, remote control of the servicers also has the consequence of a loss of reliability due to disturbances in the vicinity of the aircraft in the case where a remote control means is utilized, or a risk results of a out-out or disconnection occurring when a cable control is used.
The second refuelling method used at present and which is also the more common, relates to all airports and in particular those not equipped with a pressurized fuel distribution system. It consists of using fuel tenders also known as bowsers, which have one or more tanks for receiving the fuel, as well as equipment like that of the servicers. These fuel tenders permanently travel backwards and forwards between a storage site, often located outside the airport, and the aircraft parking points.
In view of the fact that their equipment is comparable to those of the servicers, fuel tenders suffer from the same disadvantages as the latter. Moreover, the travelling within airports of fuel tenders carrying very large quantities of fuel causes an important safety problem.
In addition to these two existing refuelling methods, EP-A-291 876 discloses a refuelling device having a trolley or truck on which is mounted a pipe or hose formed from rigid segments articulated to one another and terminated by a coupling fixable to the fuel filling port of aircraft. The opposite end of the pipe or hose can be connected to a pressure intake of a pressurized fuel distribution network. The trolley can also be equipped with means for filtering the fuel, counting means and one or more valves.
Compared with conventional refuelling methods, the use of such a device makes it possible to reduce costs and simplifies the operations which have to be carried out for refuelling an aircraft. However, a certain number of problems remain, in particular the safety problem resulting from the need of maintaining a motor in operation for driving the different energy sources, particularly hydraulic and pneumatic sources, which are installed on the trolley.